Stain removing chewing gum and confectionery compositions, and methods of making and using the same

ABSTRACT

A composition in the form of a chewing gum composition or a confectionery composition containing stain removing agent selected from anionic and non-ionic surfactants and methods of preparing and using the same to remove stains from dental material including teeth.

RELATED APPLICATION

This application claims the priority of U.S. Provisional PatentApplication Ser. No. 60/188,554 filed on Mar. 10, 2000.

FIELD OF THE INVENTION

The present invention is generally directed to chewing gum andconfectionery compositions containing an effective amount of a stainremoving component selected from anionic and non-ionic surfactants andto processes of making the compositions in a manner which facilitatesthe release of the stain removing component.

BACKGROUND OF THE INVENTION

Tooth whitening or stain removing components are known to be added todentifrice compositions such as toothpastes, mouthwashes, and the like.Such compositions include dicalcium phosphates, peroxides, percarbonatesand the like such as disclosed in, for example, U.S. Pat. Nos.5,256,402; and 5,824,291.

The employment of surfactants including non-ionic surfactants is knownfor laundry detergent compositions. Such surfactants are disclosed, forexample, in International Publication Nos. WO 92/06160 and WO 95/33034.The use of non-ionic surfactants in laundry detergent compositions isknown to improve the effectiveness of such compositions againstgreasy/oily stains.

U.S. Pat. No. 5,645,821 discloses an oral hygiene composition to cleanand whiten teeth which includes water, gelling agent, anionic surfactantand a mixture of alkaline earth metal hydroxides and carbonates. WO88/00463 discloses an oral composition for removing and/or preventingplaque and for removing stains which includes an oily compatiblesurfactant and at least one weight percent of a benzoic acid salt. Thecomposition is also stated to contain a biocide such as chlorhexidine orderivative thereof. An exemplified surfactant is sodium lauryl sulfateand the composition is also stated to contain plasticizers includingpolyethylene glycol, glycerin and the like. The reference states thatthe composition may be used in the form of dentifrices, lozenges orchewing gum.

Other chewing gum compositions and the active ingredient for removingstains disclosed therein include WO 99/43294 (chlorite ion); WO 99/27798(a water-soluble product including sodium bicarbonate and encapsulatedaspartame); Chinese Patent Document No. 1196235 (hydrogen peroxide);U.S. Pat. No. 5,824,291 (alkaline metal carbonate peroxyhydrates); WO98/29088 (cysteine proteinase); WO 98/18339 (bone minerals, calciumtriphosphate and/or hydroxyapatite); and U.S. Pat. No. 5,629,035(alkaline metal bicarbonates).

U.S. Pat. No. 4,952,407 discloses a gum composition containing a dentalplaque removing agent in the form of glycerol monolaurate. Thecomposition typically includes a high filler content wherein the filleris an inorganic material such as calcium carbonate, talc, sodiumbicarbonate dicalcium phosphate and mixtures thereof.

For coated chewing gum compositions, it is known to provide an activeagent such as a medicament in the chewing gum coating and optionally inthe core such as disclosed in WO 00/35296 and WO 00/35298.

Unlike toothpaste, mouthwash and other dentifrice compositions, gumcompositions present unique problems in delivering agents. Chewing gumcompositions typically comprise a water-insoluble gum base whichprovides the bulk to the gum composition but which invariably trapsagents having compatibility with the gum base. Adding additional amountsof an agent is problematical because the same can have an adverse effecton the integrity, sensory and/or taste properties of the gumcomposition.

It would therefore be a significant advance in the art of providing astain removing agent for the cleaning of dental material including teethif such stain removing agent could be effectively incorporated into achewing gum composition and released therefrom during the chewingprocess in a manner which provides an effective amount of the stainremoving agent. The chewing gum composition would then not only providechewing satisfaction to the user, but would also provide a beneficialdental effect.

Confectionery compositions are well known in the art. Such compositionsinclude, for example, hard boiled candies, nougats, panning goods, gelconfections, centerfill confections, fondants, and the like. Unlikechewing gum compositions which often remain in the mouth for severalminutes and often quite longer, confectionery compositions tend to havea short life in the mouth because they dissolve relatively quickly uponchewing. Nonetheless, it would be of great benefit to provideconfectionery compositions with an effective amount of a stain removingagent to provide such products to render them capable of providing abeneficial dental effect.

SUMMARY OF THE INVENTION

The present invention is generally directed to stain-removing chewinggum and confectionery compositions in which a stain removing materialhas been effectively incorporated therein so that a sufficient amount isavailable for a stain removing effect.

In a particular aspect of the present invention, there is provided astain-removing composition selected from a chewing gum composition and aconfectionery composition comprising a stain removing effective amountof at least one stain removing agent selected from the group consistingof anionic and non-ionic surfactants, said stain removing agent beingpresent in a manner which enables an effective amount of the stainremoving agent to be released from the composition.

In accordance with one aspect of the present invention, there isprovided a stain-removing chewing gum composition comprising a core anda coating comprised of at least one layer with at least one of the coreand coating comprising a stain removing effective amount of at least onestain removing agent selected from the group consisting of anionic andnon-ionic surfactants and mixtures thereof. A method of removing stainsby employing the chewing gum composition of the present invention isalso disclosed.

In a further aspect of the invention, there is provided a chewing gumcomposition in which the stain removing agent is added at a time in theprocess of making the same which enhances release of the stain removingagent during the chewing operation.

In a still further aspect of the present invention there is provided astain removing confectionery composition comprising a stain removingeffective amount of at least one stain removing agent selected from thegroup consisting of anionic and non-ionic surfactants and mixturesthereof. A method of removing stains by employing the confectionerycompositions of the present invention is also disclosed.

In a preferred form of the invention, the surfactants for both the gumand confectionery compositions are selected from the group consisting ofmedium and long chain fatty acid esters and salts, most preferablycontaining 14-20 carbon atoms, and especially sodium stearate and sodiumpalmitate and mixtures thereof, as well as a mixture of citric acidesters of mono and diglycerides.

DETAILED DESCRIPTION OF THE INVENTION

Applicants have determined that an effective stain removing chewing gumand confectionery compositions can be prepared by a suitable selectionof stain-removing agents and the formulation of the gum andconfectionery compositions and the manner in which the stain-removingagents are added to the compositions which enables the release of thestain-removing agent in an effective amount so that it may come intocontact with dental surfaces including tooth surfaces while maintainingthe organoleptic properties commonly associated with such products.

The chewing gum compositions of the present invention, may be coated oruncoated and be in the form or slabs, sticks, pellets, balls and thelike. The composition of the different forms of the chewing gumcompositions will be similar but may vary with regard to the ratio ofthe ingredients. For example, coated gum compositions may contain alower percentage of softeners. Pellets and balls have a small chewinggum core, which is then coated with either a sugar solution or asugarless solution to create a hard shell. Slabs and sticks are usuallyformulated to be softer in texture than the chewing gum core. Forpractice of the present invention however, in order to overcome anydetrimental softening effect the surfactant active may have on the gumbase, it is preferred to formulate a slab or stick gum having a firmertexture (i.e. with less softener than is typically employed).

Centerfilled gum is another common gum form. The gum portion has asimilar composition and mode of manufacture to that described above.However, the centerfill is typically an aqueous solution or gel, whichis injected into the center of the gum during processing. The stainremoving agent could optionally be incorporated into the centerfillduring manufacture of the fill or into the chewing gum. The centerfillgum may also be optionally coated and may be prepared in various formssuch as in the form of a lollipop.

For practice of the present invention it is preferred to use a coatedgum wherein the stain removing agent is in at least one of the core andthe coating. Most preferred for removing stains is a coated gum whereinthe stain removing agent is at least in the coating.

The chewing gum composition of the present invention includes gum baseand most of the other typical chewing gum composition components such assweeteners, softeners, flavorants and the like. At least one stainremoving agent is employed in the present invention which is selectedfrom anionic and non-ionic surfactants. The chewing gum composition maycontain a reduced amount of softening agents such as lecithin orglycerin or may eliminate softeners. In addition, the chewing gumcomposition may contain a larger amount of sugar alcohols thanconventional chewing gum compositions to facilitate delivery of thestain removing agent employed in the present invention to the toothsurfaces.

In accordance with one aspect of the chewing gum composition of thepresent invention, the stain removing agent is added during themanufacture of the chewing gum composition, that is, with thesweeteners, flavorants and the like. In another aspect of the presentinvention, the stain removing agent is added as one of the last steps,preferably the last step in the formation of the chewing gumcomposition. Applicants have determined that this process modificationincorporates the stain removing agent into the gum composition withoutmaterially binding the stain-removing agent therein such as may occur ifthe stain removing agent is mixed directly with the gum base. Thus, thestain-removing, while only loosely contained within the gum compositioncan be more effectively released therefrom during a typical chewingoperation. Thus a material portion of the stain removing agent is freeof the gum base.

In a further aspect of the invention, the insoluble gum base generallycomprises elastomers, elastomer plasticizers, waxes, fats, oils,emulsifiers, fillers, texturizers and may include a desirablestain-removing agent as hereinafter described.

Elastomers constitute from about 5 to 95% by weight of the base,preferably 10 to 70% by weight and most preferably 15 to 45% by weight.Examples of elastomers includes synthetic elastomers such aspolyisobutylene, polybutylene, isobutylene-isoprene co-polymers,styrene-butadiene co-polymers, polyvinylacetate and the like. Elastomersmay also include natural elastomers such as natural rubber as well asnatural gums such as jelutong, lechi caspi, perillo, massarandubabalata, chicle, gutta hang kang or mixtures thereof. Other elastomersare known to those of ordinary skill in the art.

Elastomer plasticizers modify the finished gum firmness this when usedin the gum base. Elastomer plasticizers are typically present in anamount of from about 0 to 75% by weight of the gum base, preferably fromabout 5 to 45% by weight and most preferably from about 10 to 30% byweight. Examples of elastomer plasticizers include natural rosin esterssuch as glycerol ester of partially hydrogenated rosin, glycerol esterof tall oil rosin, pentaerythritol esters of partially hydrogenatedrosin, methyl and partially hydrogenated methyl esters of rosin, and thelike. Synthetic elastomer plasticizers such as terpene resins may alsobe employed in gum base composition

Waxes include synthetic and naturally occurring waxes such aspolyethylene, bees wax, carnauba and the like. Petroleum waxes such aparaffin may also be used. The waxes may be present in the amount offrom about 0 to 30% by weight of the gum base. Waxes aid in the curingof the finished gum and help improve the release of flavor and mayextend the shelf life of the product.

Fillers modify the texture of the gum base and aid processing. Examplesof such fillers include magnesium and aluminum silicates, clay, alumina,talc, titanium oxide, cellulose polymers, and the like. Fillers aretypically present in an amount of from 1 to 60% by weight.

Examples of softeners used in gum base include hydrogenated andpartially hydrogenated vegetable oils, cocoa butter, glycerolmonostearate, glycerol triacetate, di and tri glycerides, fatty acidssuch as stearic acid, palmitic acid, oleic acid, linoleic acid,linolenic acid and the like.

The gum base constitutes between 5 and 95% by weight of the chewing gumcomposition, more typically 10 to 50% by weight, and most preferably 25to 35% by weight of the chewing gum. A higher amount of gum base ispreferred.

Other ingredients used in chewing gum compositions include sweeteners,both natural and artificial and both sugar and sugarless. Sweeteners aretypically present in the chewing gum compositions in amounts of fromabout 20 to 80% by weight, preferably from about 30 to 60% by weight.Sugarless sweeteners include, but are not limited sugar alcohols such assorbitol, mannitol, xylitol, hydrogenated starch hydrolysates, maltitoland the like may also be present. High intensity sweeteners such assucralose, aspartame, salts of acesulfame, and the like. High intensitysweeteners are typically present from about 0 to 1.0% by weight.

Flavoring agents which can vary over a wide range may be selected inamounts from about 0.1 to 10.0% by weight, preferably from about 0.5 to5.0% by weight. Flavoring agents for use in chewing gum compositions arewell known and include citrus oils, peppermint oil, spearmint oil, oilof wintergreen, menthol and the like.

Softeners may be present to modify the texture of the chewing gumcomposition. Unlike typical gum compositions, softeners in thecompositions of the present invention are typically present in reducedamounts of from about 0.5 to 10% by weight based on the total weight ofthe chewing gum.

Other materials which may be present in the gum composition of thepresent invention include antioxidants (e.g. butylated hydroxyanisole,butylated hydroxytoluene, beta-carotenes, tocopherols, colorants,flavorants and the like.

Coating techniques for applying a coating for a chewing gum compositionsuch as pan and spray coating are well known. Preferred in the practiceof the present invention is coating with solutions adapted to build ahard candy layer. Both sugar and sugar alcohols may be used for thispurpose together with high intensity sweeteners, colorants, flavorantsand binders. When the stain removing agent is provided in the coating ofa chewing gum composition, a solution of the stain removing agent ispreferably, alternately, applied with the flavorant.

The sweetener may be present in an amount of from about 30% to about 80%by weight of the coating syrup. The binder may be present in an amountof from about 1% to about 15% by weight of the coating syrup. Minoramounts of the optional additives may also be present. The sweetenerssuitable for use in the coating syrup comprise sugarless sweeteners suchas the polyhydric alcohols, e.g., xylitol, sorbitol, mannitol, andmixtures, thereof; as well as maltitol, isomaltitol, hydrogenated starchhydrolysates, and hydrogenated glucose syrups. Mono, di- andpolysaccharide may also be included. For example, sugars such assucrose, fructose, glucose, galatose and maltose may also be employed asa sweetener. Other sweeteners suitable for use in the coating syrupinclude, but are not limited to free saccharin acid, water soluble saltsof saccharin, cyclamate salts, palatinit dihydrochalcones, glycyrrhizin,L-aspartyl-L-phenylalanine methyl ester, amino acid based sweeteners,talin, steviosides, dihydrochalcone compounds, acesulfame salts andmixtures thereof.

Other components may be added in minor amounts to the coating syrup andinclude moisture absorbing compounds, anti-adherent compounds,dispersing agents and film forming agents. The moisture absorbingcompounds suitable for use in the coating syrups include mannitol ordicalcium phosphate. Examples of useful anti-adherent compounds, whichmay also function as a filler, include talc, magnesium trisilicate andcalcium carbonate. These ingredients may be employed in amounts of about0.5% to about 5% by weight of the syrup. Examples of dispersing agentswhich may be employed in the coating syrup include titanium dioxide,talc or other anti-adherent compounds as set forth above.

The coating syrup is usually heated and a portion thereof deposited onthe cores. Usually a single deposition of the coating syrup is notsufficient to provide the desired amount or thickness of coating and itusually will be necessary to apply second, third or more coats of thecoating syrup in order to build up the weight and thickness of thecoating to desired levels with layers allowed to dry in-between coats.

A preferred aspect of the chewing gum composition invention adds a stainremoving agent to the coat. The stain removing agent is preferablyapplied subsequent to the syrup coating. It is preferred to then apply acoat of high intensity sweetener prior to coating with the stainremoving agent. Application of the stain removing agent is preferablydone alternatively to application of a flavorant solution. In thepractice of the present invention the stain removing agent may beapplied as a solution or may be applied as a dry charge or, whereapplicable, melted and applied. For fatty acid salts a dry charge may bepreferred. In coating a chewing gum composition, the applications ofcoating syrup are continued until the average gum piece weight reachesthe required coating weight, preferably until the coat comprises 20-30%by weight of the final pellet weight.

The present invention also encompasses confectionery compositionscontaining a suitable selection of stain-removing agents. Confectionerycompositions include compressed tablets such as mints, hard boiledcandies, nougats, gels, centerfill confections, fondants, panning goodsand other compositions falling within the generally accepted definitionof confectionery compositions.

Confectionery compositions in the form of pressed tablets such as mintsmay generally be made by combining finely sifted sugar or sugarsubstitute, flavoring agent (e.g. peppermint flavor) bulking agent suchas gum arabic, and an optional coloring agent. The flavoring agent,bulking agent are combined and then gradually the sugar or sugarsubstitute are added along with a coloring agent if needed.

The product is then granulated by passing through a seize of desiredmesh size (e.g. 12 mesh) and then dried at typically 55 to 60° C. Theresulting powder is fed into a tableting machine fitted with a largesize punch and the resulting pellets are broken into granules and thenpressed.

High boiled candies typically contain sugar or sugar substitute,glucose, water, flavoring agent and optional coloring agent. The sugaris dissolved in the water and glucose is then added. The mixture isbrought to a boil. The resulting liquid to which may previously havebeen added a coloring agent is poured onto an oiled slab and cooled. Theflavoring agent are then added and kneaded into the cooled mass. Theresulting mixture is then fed to a drop roller assembly known in the artto form the final hard candy shape.

A nougat composition typically includes two principal components, a highboiled candy and a frappe. By way of example, egg albumen or substitutethereof is combined with water and whisked to form a light foam. Sugarand glucose are added to water and boiled typically at about 130-140° C.and the resulting boiled product is poured into a mixing machine andbeat until creamy.

The beaten albumen and flavoring agent are combined with the creamyproduct and the combination is thereafter thoroughly mixed.

Further details regarding the preparation of confectionery compositionscan be found in Skuse's Complete Confectioner (13^(th) Edition) (1957)including pp. 41-71, 133-144, and 255-262; and Sugar ConfectioneryManufacture (2^(nd) Edition) (1995), E. B. Jackson, Editor, pp.129-168,169-188, 189-216, 218-234, and 236-258 each of which is incorporatedherein by reference.

In accordance with the present invention, a stain-removing effectiveamount of an anionic and/or non-ionic surfactant is employed as astain-removing agent for chewing gum and confectionery compositions.Typical examples of the stain removing agents which may be employed inthe present invention include sulfated butyl oleate, medium and longchain fatty acid esters and salts in particular the sodium and potassiumsalts of the stearate and palmitate, and methyl and ethyl estersthereof, sodium oleate, salts of fumaric acid, potassium glomate,organic acid esters of mono and diglycerides such as stearylmonoglyceridyl citrate, succistearin, dioctyl sodium sulfosuccinate,glycerol tristearate, lecithin, hydroxylated lecithin, sodium laurylsulfate, acetylated monoglycerides, succinylated monoglycerides,monoglyceride citrate, ethoxylated mono- and diglycerides, sorbitanmonostearate, calcium stearyl-2-lactylate, sodium stearyl lactylate,lactylated fatty acid esters of glycerol and propylene glycerol,glycerol-lactoesters of C14-C20 fatty acids, polyglycerol esters ofC14-C20 fatty acids, propylene glycol alginate, sucrose C14-C20 fattyacid esters, diacetyl tartaric or citric acid esters of mono anddiglycerides, triacetin and the like and mixtures thereof.

The preferred surfactants for use in chewing gum compositions of thepresent invention are sodium stearate, usually available as anapproximate 50/50 mixture with sodium palmitate, and, a mixture of atleast one citric acid ester of mono and/or diglycerides. A suitableexample of a commercial stain removing agent in the latter class isIMWITOR 370® sold by Condea Vista Company. The amount of thestain-removing agent for chewing gum compositions is typically fromabout 0.2 to 2.0% by weight based on the total weight of the chewing gumcomposition. The preferred amount of the stain-removing agent is fromabout 0.4 to 1.2% by weight. The amount of the stain removing agent willvary depending upon the particular individual or combination ofstain-removing agents employed. For example, a preferred amount ofsodium stearate is about 0.5% by weight, while a preferred amount of amixture of citric acid esters of mono- and diglycerides (IMWITOR 370®)is about 1% by weight.

The preferred stain removing agents for use in the confectionerycompositions of the present invention are sodium stearate, sodiumpalmitate and mixtures thereof. As indicated in connection with thechewing gum compositions, sodium stearate is usually available as anapproximately evenly divided mixture with sodium palmitate.

The amount of the stain removing agent which may be employed in theconfectionery compositions of the present invention will vary over arange depending on, for example, the type of confectionery compositionand the particular individual or combination of stain removing agentswhich are employed. Generally, the amount of stain removing agent usedin the confectionery compositions of the present invention will exceedthe amount of the stain removing agent employed for the chewing gumcomposition for a particular stain removing agent.

Typically, the stain removing agent for confectionery compositions willbe present in an amount of from about 0.2 to 20% by weight based on thetotal weight of the confectionery composition. The preferred amount ofthe stain removing agent is from about 3 to 15% by weight.

EXAMPLES

The following examples are submitted for illustrative purposes only andare not intended to limit the scope of the application as fully coveredby the specification and claims.

Example 1: Preparation of Gum Products A. Slab Gums

TABLE 1 Ingredient Sample 1 Sample 2 Gum base 29.75 29.75 Atomite(Filler) 4.2500 4.2500 Sorbitol 49.9868 49.4868 Mannitol 10.00 10.00Glycerin 1.00 1.00 High Intensity sweetener* 1.3632 1.3632 Flavor 3.15003.1500 Sodium stearate** 0.500 — IMWITOR370 ® — 1.00 Totals 100.00100.00 *Aspartame Ace K mixtures **Sodium stearate/sodium palmitate @50/50

Samples 1 and 2 of the chewing gum compositions identified in Table 1were prepared by conventional methods. The gum base was heated tosufficiently soften the base without adversely affecting the physicaland chemical make up of the base. The molten gum base and the fillerwere then added to a mixing kettle. The sugar alcohols, glycerin,flavor, high intensity sweetener and stain removing agent were addedwith mixing to obtain a homogenous mixture, with the stain removingagent added last. The mixture was then discharged from the mixing kettleand rolled and scored into a desired piece size by conventionaltechniques.

B. Coated Gums—Stain Moving Agent in Coat

TABLE 2 Ingredient Sample 3 Sample 4 Sample 5 Core Gum Gum Base 26.25026.250 26.250 Atomite (Filler) 3.750 3.750 3.750 Sorbitol 33.525 33.52533.5250 Mannitol 7.500 7.500 7.500 Flavorant 2.8075 2.8075 2.8075Glycerin 1.00 1.00 1.00 High Intensity Sweetener* 0.7875 0.7875 0.7875Coat Maltitol 22.1228 21.6228 22.1228 Ace-K 0.0350 0.0350 0.0350Flavorant 0.343 0.343 0.343 Gum Arabic 1.1678 1.1678 1.1678 TitaniumDioxide 0.1780 0.1780 0.1780 Candelilla Wax 0.0334 0.0334 0.0334 Sodiumstearate** 0.500 — — IMWITOR 370 ® — 1.00 — Sodium Oleate — — 0.5000Total 100.00 100.00 100.00 *Aspartame Ace K mixtures **Sodiumstearate/palmitate @ 50/50

Gum cores were prepared by the same conventional methods as in part Aherein. The molten gum base and the filler were added to the mixingkettle and mixing was commenced. The sugar alcohols, glycerin, flavors,and high intensity sweetener mixture, were added in portions with mixingto obtain a homogenous mixture. The mixture was then discharged from themixing kettle and formed into cores by conventional techniques.

The cores were placed into a coating pan and broken into individualpieces as necessary. A sugarless solution containing 70% by weight ofmaltitol, as well as titanium dioxide, gum arabic and water was heatedto between 70° and 80° C. The solution was sprayed onto the gum corepieces in layers and allowed to dry between sprays while the coating panwas continually rotating to ensure a smooth even coat of the gum cores.

The coating was built up to about 8% by weight of the final pelletweight. Ace-K was then added and then covered with another layer of theabove-mentioned coating solution and then allowed to dry.

A 20% solution of the stain removing agent identified in Table 2 wasprepared by heating water to between 65° and 75° C. and then slowlyadding the stain removing agent. The solution was mixed under lowagitation to avoid foaming until a clear solution was obtained. Thesolution was maintained at the same temperature for the entire coatingprocedure.

After the high intensity sweetener layer was dried, the solutioncontaining the stain removing agent and a flavorant were added inalternating layers until all of the respective materials were added witheach layer being allowed to dry before the next layer was applied. Thecoating process continued with the coating solution until the coatcomprised 24% by weight of the final pellet weight.

The coating was then topped with a conventional finishing solution untila shell weight of 25% by weight was obtained. The pellets were thenpolished in a polishing pan with candelilla wax in a convention manner.

C. Coated Gums—Stain Removing Agent in Core

TABLE 3 Ingredient Sample 6 Core Gum Gum Base 26.250 Atomite (Filler)3.750 Sorbitol 32.962 Mannitol 7.500 Glycerin 1.00 Flavorant 2.8075 HighIntensity Sweetener* 0.7875 Sodium stearate** 0.563 Coat Flavorant 0.343Ace-K 0.0350 Maltitol 22.6228 Gum Arabic 1.1678 Titanium Dioxide 0.1780Candelilla Wax 0.0334 Total 100.00 *Aspartame, Ace K mixtures **Sodiumstearate/palmitate @ 50/50

Gum cores were prepared by the same conventional methods as the slab gumin part A herein with the stain removing agent being added last. Themixture was then discharged from the mixing kettle and formed into coresby conventional techniques.

The cores were placed into a coating pan and coated as in Part B hereinwith the exception that the application of a stain removingagent-containing layer was eliminated from the process.

Example 2: Efficacy Tests of Gum Products A. Mechanical Chew Test

Chewing gum Sample 6, as prepared as in Example 1, was tested in anin-vitro mechanical chewing model. A commercial whitening pellet-typegum containing sodium bicarbonate was used as a control. The gum sampleswere masticated by the chewing machine, which contained stained bovineteeth on the chewing surfaces to simulate the top and bottom teeth in ahuman mouth. The samples were chewed for five minutes. The bovine toothsamples were read with a Chrom-A-Meter before they were placed in themachine and after a simulated one week of chewing (28 doses). The colorchange is then determined by calculating the DE value. All of the stainis then removed from the bovine tooth samples and read again with theChrom-A-Meter. The percent stain reduction is then calculated. Theresults are presented in Table 4.

TABLE 4 Stain Reduction Control Sample 6 % Stain Reduction 11.9% 34.1%

The test shows that Sample 6 provided a reduction in the occurrence ofstaining after the test period when compared to a commercial toothwhitening gum.

B. Clinical Tests

Test I:. Sixty individuals were divided into 4 groups of 15 individualseach. Group I received no treatment. Group II received the chewing gumcomposition of Sample 3, and Group III received the chewing gumcomposition of Sample 5 while Group IV acted as a control and receivedthe commercial pellet-type tooth whitening chewing gum containing sodiumbicarbonate mentioned above.

Each of the individuals used the chewing gum after meals and thestaining effect was observed after 2 and 4 week periods. The results areshown in Table 5.

TABLE 5 Stain Scores* Stain Scores No Treatment Sample 3 Sample 5Control Baseline 1.04 1.04 1.04 1.04 2 week 1.09 0.93 1.02 1.06 4 week1.43 1.30 1.24 1.38 *McPhearson Modification of the Lobene stain index

As shown in Table 5, Samples 3 and 5 provided a reduction in theoccurrence of staining after the 4 week test period when compared to notreatment group and to the commercial pellet-type tooth whitening gumcontaining bicarbonate mentioned above.

Test II:. Two hundred individuals were divided into 4 groups of 50individuals each. Group I received no treatment. Group II received thechewing gum composition of Sample 3, Group III received the chewing gumcomposition of Sample 4 while Group IV received the chewing gumcomposition of Sample 6.

Each of the individuals used the chewing gum after meals and the stainremoving effect was observed after 4 to 8 week periods. The results areshown in Table 6.

TABLE 6 Stain Reduction 4 Week No Treatment Sample 3 Sample 4 Sample 6p-value() 0.904 <0.001 0.002 <0.001 Baseline) % Change 0.40 13.68 8.307.35 8 Week No treatment Sample 3 Sample 4 Sample 6 p-value() 0.056<0.001 0.002 <0.001 Baseline) % Change −5.67 20.17 10.04 14.29

TABLE 7 Pair Comparison 4 Week Sample 3 Sample 4 Sample 6 No Gum <0.0010.010 0.018 Sample 3 — 0.133 0.062 Sample 4 — — 0.755 8 Week Sample 3Sample 4 Sample 6 No Gum <0.001 <0.001 <0.001 Sample 3 — 0.044 0.258sample 4 — — 0.319

As shown in Tables 6 and 7, the chewing gum composition of Samples 3, 4and 6 exhibited a significant stain removing effect when compared to theno treatment group.

Example 3: Preparation of Pressed Mint Products Sample 1

A 2000 batch of a composition for forming a pressed mint product inaccordance with the present invention is prepared in the followingmanner.

Sorbitol 98.0% by weight, 0.5% by weight of silicon dioxide, 0.3% byweight of a flavoring agent, and 0.7% of Aspartame are mixed for twominutes in a blender until a homogenous mixture is obtained. Sodiumstearate 0.1% by weight is added to the mixture which is then blendedfor four minutes. The resulting mixture is then formed into individualpressed tablets in a conventional manner.

Samples 2 and 3

The procedure set forth in Sample 1 is repeated except that the amountof sodium stearate is increased to 0.5% (Sample 2) and 3.0% (Sample 3),respectively with a corresponding reduction in the amount of sorbitol.

Sample 4 and Control

The procedure of Sample 1 was repeated for forming pressed tabletcompositions containing the ingredients shown in Table 8.

TABLE 8 INGREDIENT SAMPLE 4 CONTROL Sorbitol Powder 96.622 99.622Aspartame 0.100 0.100 Acesulfame Potassium Salt 0.050 0.050 Flavorant0.228 0.228 Sodium Stearate 3.000 —

Example 4: Efficacy Tests of Pressed Mint Products

The pressed tablets produced in accordance with Sample 4 and the controlexample were tested to determine their ability to remove stains fromhydroxyapatite disks.

Deionized water 400 ml was heated to and maintained at 37° C. under astirring with a stirring bar operating at 300 rpm. Two stainedhydroxyapatite disks were suspended in the water. The test mints weredropped into the water and allowed to dissolve. As soon as the mintswere dissolved the disks were removed from the test solution. Theprocedure was repeated for varying mint weight/dissolution times. Thedisks were read before and after treatment with a Chrom-A-Meter and thedifference was calculated. This procedure was repeated using deionizedwater alone and the difference calculated between before and aftertreatment. The test samples were compared to the control sample and tothe water as a control and the % difference in stain reduction wascalculated. The results are shown in Table 9.

TABLE 9 Weight/Dissolution Time Water Control 1.0 g/3 min. 84 52 1.5 g/4min. 45 31 1.75 g/4.5 min. 101 26 2.0 g/5 min. 56 11 2.25 g/5 min. 81 22

The results shown in Table 9 show the percent improvement in stainreduction associated with Sample 4 as compared with water alone and thecontrol mint composition having no stain removing agent present.

What is claimed is:
 1. A stain removing chewing gum compositioncomprising a core and coating having at least one layer, at least thecoating comprising a stain removing effective amount of a stain removingagent selected from the group consisting of sodium stearate, sodiumpalmitate and mixtures thereof.
 2. The stain removing chewing gumcomposition of claim 1 wherein the chewing gum composition is in theform of a slab or stick, said chewing gum composition having a reducedamount of a softener.
 3. The stain removing chewing gum composition ofclaim 1 wherein the chewing gum composition is a centerfill chewing gumcomposition having a centerfill and a gum portion, said stain removingagent being present in the centerfill, the gum portion or both.
 4. Thestain removing chewing gum composition of claim 1 wherein the stainremoving agent is present in the coating only.
 5. The stain removingchewing gum composition of claim 1 wherein the stain removing agent ispresent in the coating and the core.
 6. The stain removing chewing gumcomposition of claim 1 wherein the amount of the stain removing agent isfrom about 0.2 to 2.0% by weight based on the total weight of thechewing gum composition.
 7. The stain removing chewing gum compositionof claim 6 wherein the amount of the stain removing agent is from about0.4 to 1.2% by weight based on the total weight of the chewing gumcomposition.
 8. The stain removing chewing gum composition of claim 6wherein the stain removing agent is a 50/50 mixture of sodium stearateand sodium palmitate and the amount of the stain removing agent is about0.5% by weight based on the total weight of the chewing gum composition.9. A method of removing stains from teeth comprising chewing aneffective amount of the stain removing chewing gum composition ofclaim
 1. 10. A method of producing the stain-removing chewing gumcomposition of claim 1 comprising adding the stain removing agent to thecoating in one of the last steps of forming the chewing gum compositionto enable the stain removing agent to be loosely contained within thechewing gum composition whereby the stain removing agent can beeffectively released upon chewing.